intermittant problem w/ posts and replies

Even though my .slrnrc file shows

set save_posts"/home/holtzm/mail/slrn_posts"
set save_replies "/home/holtzm/mail/slrn_replies"

and the lines for "News/My_Posts" and "News/My_Replies" are commented
out, I sometimes experience failures to write to $HOME/mail/slrn_replies
and $HOME/mail/slrn_posts. When that happens I get an error message, the
latest being

Error writing to News/My_Replies 

Can anyone shed some light on this? I'm running slrn 1.0.0~pre18-1.1 on
Debian Squeeze but the problem also occurs on Ubuntu Lucid.

-- 
Bob Holtzman
If you think you're getting free lunch, 
chech the price of the beer.
Key ID: 8D549279

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